Truing mechanism



0t 5, 1931- L. F. NENNINGER 1,825,753

TRUING MECHANISM Filed Feb. 17, 1926 2 Sheets-Sheet 1 Oct. 6, 1931.

1 F. NENNINGER 1,825,753

TRUING MECHANI SM Filed Feb. 17, 1926 2 Sheets-Sheet 2 Invalidez QJZJ/emn'nyer @M www Patented Oct. 6, 1931 UNITED STATES PATENT OFFICE LESTER F. NENNINGER, F CINCINNATI, OHIO, ASSIGNOR, BY MESNE ASSIGNMENTS, T0 CINCINNATI GRINDERS INCORPORATED, 0F lCINClNNATLOHO, A CORPORATION OF OHIO TR'UING MECHANISM Application led February 17, 1926. Serial'No. 88,960.

This invention relates to improvements in grinding machinery and. more particularly to a truing fixture for use in connection therewith. Y Y

; One ofthe most important forms of grinding machinery of the present day is what 1s known as the centerless grinder which broadly considered comprises opposed grinding and regulating wheels and an intermediate workrest. This 'machine is used both for thru feed grinding and for form grinding of workpieces ofcylindrical form incro-sssection. The present truing mechanism is particularly designed for use in connection with centerless grinding machinery although capable of application to ordinay single wheel grinders or the like. i

An object of the present invention is the provision of a simple and compact truing l mechanism which may be readily applied to a grinding machine and which will eiciently produce on the grinding face of the wheel the desired transverse configuration.

A further obj ect of the invention is the provision of a mechanism which may be readily modified to vary the surface configuration produced therebya Another object of the invention is the provision of an improved template-supporting 3o means whereby the angular relationship of the transverse configuration may be varied as /desired with regards to the axis of rotation of the grinding member.

Other objects of the invention include improvements in manner of adjustment and securing of the several parts and a general structural simplification and should be readily apparent by reference to the following specification taken in connection with the accompanying drawings. It will be understood that any modifications in the specific details .illustrated within the scope of the appended claim may be made without departing from or exceeding the spirit of the invention.

Figure 1 is a front view of a centerless grinder with the improved truing mechanism applied thereto.

5@ Figure 2 is a view partly in plan and partly in section taken on the line 2-2 of Figure 1.

Figure 3 is a vertical section.

Figure 4 is a fragmentary section on the line 4-4 of Figure 3, and

Figure 5 is a vertical section on the line 5-5 of Figure 3.

E is located. This mechanism includes a base 10 mounted on bracket F and having the transverse guides 1l and 12 for the carriage 13. Lug. 14 on member 10 rotatably supports feed screw 15 having the hand wheel 16. This screw is engaged in ad- ]ustin'g nut 17 set into carriage 13to 'control' the transverse reciprocation thereof. The carriage is in turn provided with the dovetail slot 18 for the guides 19 of slide 20. This slide is provided with the bore 21 to receive the sleeve or bushing 22, said parts being suitably secured together against accidental longitudinal or rotative movement as 'byvclamp 51.

Within bushing 22 is the truing tool holder 23 keyed as at 24 for longitudinal sliding but held against rotative movement. This axial shifting of the holder is to compensate for the wearing away ofthe surface of the grinding wheel during grinding and truing operations. A suitable means for effecting such adjustment is illustrated and consists of the screw 124 threaded into the socket 25 in the outer end of spindle 23. This screw is swiveled in block 26 secured in the outer end of the bushing 22 and is providedon its outer projecting end with head 27 having handle p0rtion 28 to facilitate rota-tion thereof'.

It will thus be noted that the slide has an in and out movement as an entirety and the tool spindle a movement relative to the slide. The movement of the spindle is intended to compensatefor wear of the wheel while movement of the slide is to produce desired configuration on the surface of the abrasive wheel E. The movement of 4the slide is preferably controlled by suitable template mechanism such as illustrated. The base portion 10 of the device is formed with a pivot stud 29 on which is swiveled block 30 adapted to be secured in adjusted position about the fulcrum by suitably, loosening and tightening of the pair of screws 31-32 in upstanding lugs on base 10 adjacent the block 30. The block may be placed in a position parallel with the axis of the wheel to be trued or at any desired angle thereto. Removably secured to' the block as by bolts 33 is the template portion 34 illustrated as an angular l member having the contoured surface 35 correspondin in outline to the cross-sectional contour `w ich it is desired to reproduce on the opposite ortion of the grinding wheel.

' In order t at the-truing tool may follow the shape of the template most accurately,

j slide 20 is provided with aperture 36 for fol-I lower member 37 locked in ositionby set screw 38 and having the kni e edge contact portion 39 adapted to ride on the contour ace 35 of the template. To retain the slide Contact 39 in close engagement with face'35 of the template, plunger 40 is movably suprted in slide 20 and has contact roller 41 aring against the template in opposition to contact 39. Member 40 isv rovided with shoulder 42 While interposed etween shoulder 42 and a portion of slide 20 is expansion spring 43 outwardly urging the plungerin the direction of the follower.

It is to be understood in grinding operations use is ordinarily made of a suitable coolant supplied as thru the pipe G shown 1n Figure 1. To prevent undue amount of this coolantbeing thrown off by centrifugal action when the machine is in use, a wheel housing H is ordinarily provided.- This housing is shown as formed with the slot 44 thru which the truing spindle 23 and bushing 22 extend, while encircling bushing 22 is cover plate 45 having a bent portion 46 slidable in kerf 47 of the housing. The interengagement of thefiange 46 thus formed on the shield 45 with the walls of the kerf or slot 47 in member H retain the parts in interlocking engagement accentuated by the weight of member 45 resting on the slide way or face formed therefor on the member H. As the bushing 22 projects inward through a suitable aperture in the member 45 the shield is laterally reciprocated therewith. In this way the aperture thru which the truing tool operates is lsealed against egress of the cpolant.

In the use of this mechanism the member 124 is rotated, moving spindle 23 inward until the diamond or truing point 50 is in proper engagement with the surface of the stone as shown in Figure 2. If the movement of the tool is insuilicient, clamp 51 may be loosened and bushing 22 and the tool spindle inwardly shifted as an entirety, and the fine adjustment of the parts subsequently completed by use of' adjusting screw 24. The template of proper contour is secured to block 30 and screws 31-32 are adjusted to brin the block and template in proper relations ip to the stone surface.r Rotation of hand wheel 16 and consequent actuation of adjusting screw 15 serves to impart a back and forthA movement to carriage 13 causing the truing tool to traverse the operative face ofthe grinding wheel while moving in and out in accordance with the interengagement of knife edge 39 of the follower and contoured edge. 35 of the template. Slight inward adjustments of the tool 'spindle may be made relative to the bushing during the truing operation to compensate for material removed from the grinding wheel. l

Particular attention is invited to the fact that the ivot 29 is laterally off-set with respect to siide 13 and substantially in the plane thereof so that the angularly adjustable block 30 is correspondingly located. Further to the fact that the templet member 34 is in the form of an angle plate secured to the inner face of said block and projecting upward thereabove for proper engagement with the fixed follower 39 on the truing device and the resiliently pressed roller or plunger 41 and that the templet block provldes a plain or non-contoured inner face for continuous movement therealong of the resiliently actuated follower on the. one side together with an opposed contoured face on the opposite side for engagement by the fixed follower.

Also, that the rearward or reverse extension of the templet member is suchthat its contoured portion overlies the pivoted member in spaced relation to the supporting block so that the fixed follower itself passes across the center of pivotance during itstraverse movement. The projection of the templet above the block is such as to insure ready clearance of the fixed follower member while its extension in overlying relation to the pivot and substantially to the `center of pivotance or angular-.adjustment of the templet serves to minimize the in and out movement of the truing device at its central position for various angular adjustments of the templet.

- I claim:

A mechanism of the character described includin a base or support, a carriage transversely s iftable thereon, a slide mounted on the carriage for in` and out movement relative to carriage and base, means for imparting in and out movement to the slide during transverse movement of the carriage, said means including a template carried by the base, a follower carried by the slide for engagement with the template and a springpressed plunger carried by the slide and engaging the template in opposition to the Contact for retaining the parts in operative relation, a tool-holding sleeve adjustably mounted on the slide, a'truing tool carried thereby for adjustment therewith and relative thereto, and a shield member carried by said support and encircling the sleeve,

said shield being transversely shiftable with the sleeve on movement of the carriage.

LESTER F. NENNINGER. 

